Jeannine,
I would suggest you read Tooby and Cosmides, Psychological
Foundations of Culture, in Barkow Cosmides and Tooby "the adapted Mind"
if these issues interest you.
Try too Dawkins blind watchmaker and George Williams Ev. and nat. selection.
It will go a long way toward clearing up the issues you are thinking
about. A friendly ditto to others who are thinking along the same lines
as Jeannine.
Larry